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151.
The key to soil spray-sowing technology is the use of the highly-effective rock-corroding strains, and the mechanism of rock corrosion will provide theoretical references to screen the strains. To investigate the corrosion mechanism of limestone by microorganisms, the dominant and highly-effective limestone-corroding strain Gongronella butleri NL-15 was isolated and purified from the microorganisms on the rock surface. The concentration of calcium (Ca), magnesium (Mg), potassium, and phosphorus was analyzed by ICP. The pH of the fermentation broth of the strain at different intervals was measured using a precise pH instrument. The content of organic acids (critic, succinic, lactic, fumaric, acetic, and propanoic acids) and the scanning electron microscope feature of rock particles in the fermentation broth at different intervals were also analyzed by HPLC. The results showed that the concentration of Ca2+ and Mg2+ in the fermentation broth correlated negatively with the pH value (P < 0.01). The pH of control was 6.87, and that of the fermentation broth after 15 days dropped to 5.12. The concentration of Ca and Mg was 38.96 and 10.85 mg/L respectively, whereas that of the fermentation broth after 15 days increased to 367.56 and 76.16 mg/L respectively. The content of the total organic acids and lactic acid increased with increase in fermentation time. The content of the total organic acids on days 2, 5, 9, and 15 in the fermentation broth was 3.43, 5.40, 6.63, and 7.26 mg/mL, respectively, and the content of lactic acid was 1.79, 2.85, 5.16, and 5.04 mg/mL, respectively. The mycelium of the G. butleri NL-15 adhered to the surface of rock particles and threaded into unconsolidated rocks. Thus, the organic acids, especially lactic acid produced by the fungi G. butleri NL-15, caused unconsolidation of rock and improved the growth of fungi mycelium into the unconsolidated rock. This was the primary cause for limestone corrosion, and the release of Ca and Mg from the rock and its disintegration. © 2018 Science Press. All rights reserved. 相似文献
152.
Pyrolysis is an alternative technology for oil sludge treatment. Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy and Pyrolysis-Gas Chromatography/Mass Spectrometry were employed to investigate the pyrolysis process and products of oil sludge. The pyrolysis process was divided into five stages: drying and gas desorption, oil volatilization, main pyrolysis, semi-coke charring, and mineral decomposition. The main reaction temperatures ranged from 497.6 K to 753.2 K. The products were mainly composed of pairs of alkane and alkene (carbon number ranges from 1 to 27). The mechanisms consisted of random chain scission followed by end chain scission at high temperatures with volatilization occurring during the whole process. This study is useful not only for the proper design of a pyrolysis system, but also for improving the utilization of liquid oil products. 相似文献
153.
Odor pollution caused by municipal solid waste (MSW) treatment plants has become a growing public concern. Although aerobic pretreatment of MSW has advantages in accelerating landfill stabilization, the property of non-methane organic compound (NMOC) emissions from aerobically pretreated MSW (APMSW) during landfilling is unknown. To investigate NMOC emissions from anaerobic degradation of APMSW and to study the impact of organic compositions of APMSW and their decomposition stages, five simulative anaerobic bioreactors (R1-R5) were filled up with APMSW of different original organic compositions in a laboratory. For NMOC analysis, samples were collected from the gas that accumulated separately during two successive independent stages of the whole experiment. The results showed that the cumulative quantities of NMOCs from R1 to R5 were 1.11, 0.30, 0.18, 0.28, and 0.31 mg/kg DM, respectively, when volatile solid was degraded by 34.8-47.2%. As the organic content of the original waste was lower, the proportion of NMOCs generated in the early stage of anaerobic degradation became higher. Multiple linear regression analyses of the relationship between the quantities of degraded organics and generated NMOCs showed that lipid and protein have a strong effect on NMOC amount. The effect of lipid on NMOC quantity lasts longer than that of protein. This observation suggests that controlling the lipid and protein contents in MSW can reduce the odor from landfills. 相似文献
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利用原子吸收分光光度计分析了寄生鳜鱼(Sinipercachuatsi)鳃部的河鲈锚首吸虫(Ancyrocephalusmogurndae)及其宿主组织器官,包括肌肉、鳃、头肾和肝脏的铅含量.结果表明,来自三湖连江水库和牛山湖两个采样点的河鲈锚首吸虫的铅含量都显著地高于其宿主组织器官中的铅含量.在所检测的宿主组织器官中,肝脏的铅含量最高,在两个采样点分别为0.138和0.114μg/g(湿重).河鲈锚首吸虫富集铅的机理及其较高水平铅含量的特点是否与其体外寄生的特性有关,尚有待于进一步研究. 相似文献
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158.
利用含油碳酸钙污泥制备橡胶填充剂 总被引:3,自引:0,他引:3
本文以中原油田含油碳酸钙污泥为研究对象,根据高分子理论化学和橡胶工程理论,论证了油田含油碳酸钙污泥开发含油橡胶填充剂的理论基础。经粉体加工,将含油碳酸钙污泥制备成实验用橡胶填充剂。通过橡胶工程实验及产品测试,结果表明,与正在使用的普通碳酸钙和纳米碳酸钙填充剂相比,含油碳酸钙污泥制备的填充剂对橡胶制品的性能没有明显的影响;在分散性、橡胶网状分子的交联性、磨耗、回弹性等方面,较普通碳酸钙和纳米碳酸钙的填充效果稍优。 相似文献
159.
Hanzhong Jia Yafang Shi Xiaofeng Nie Song Zhao Tiecheng Wang Virender K. Sharma 《Frontiers of Environmental Science & Engineering》2020,14(4):73
160.
通过实验数据分析,对本源微生物菌剂处理印染废水的有效性进行了检验。在此基础上,确定了先生物处理后絮凝的处理方式。进而分析了印染废水原处理工艺中存在的问题,并对其进行了改造,即:以本源微生物菌剂为母菌接种于印染废水中,并结合生物铁填料对其进行处理。工艺改造成功启动后,稳定运行结果显示:复合生化池和接触氧化池的处理工艺对色度和COD的平均去除率分别为:55.69%、55.63%和78.53%、78.21%;出水pH、色度和COD的平均值分别为6.6、13倍和93 mg/L,全部满足标准要求。该工艺大大减少了污泥量,且降低了处理费用。 相似文献